1. Field of the Invention
The invention relates to a hatch in a fixed roof surface of a motor vehicle with a frame which is located in a roof cutout in the roof surface, with a cover which can be opened and closed relative to the frame via a raising mechanism and with an actuating means for the raising means.
2. Description of Related Art
Hatches of the type to which the invention is directed are contained in the fixed roof surfaces of commercial vehicles such as busses and the like, or in trailers. They are used to ventilate the vehicle interior and can also be made as emergency exit means, for example, in busses based on legal regulations. The hatches conventionally contain a frame which is located in the roof cutout of the roof surface and a cover which opens and closes relative to this frame.
German Patent DE 40 11 903 C1 describes a motor vehicle roof having a fixed roof surface in which there is a roof opening which can be opened and closed by means of a cover. The cover is connected via two axes which run transversely to the lengthwise direction of the vehicle via a pivot bearing and a raising mechanism with a frame which is inserted into the roof opening. As the actuating means, there is a control element which is located centrally on the cover, which can turn around its axis and which actuates the raising mechanism located on the cover.
Published German Patent Application DE 19747861 A1 discloses a hatch for stationary use in buildings which can be raised on one side by means of a hydraulic cylinder which acts on a toggle lever mechanism.
The primary object of the present invention is to devise a hatch of the initially mentioned type which has a simpler structure and an improved actuating mechanism.
This object is achieved in accordance with the invention by the raising mechanism having two toggle joints which are supported on the frame to raise one edge of the cover and two toggle joints which are supported on the frame to raise an opposite edge of the cover, and by the actuating mechanism having a transmission which can be moved along the frame, which is guided on the frame, and to which actuating elements are attached for simultaneous actuation of the two pairs of toggle joints.
Thus, in this hatch, the raising mechanism, the actuating mechanism and the movable transmission are located on the frame so that, on the cover, there need be only holding devices for connecting the cover to the toggle joint. Therefore, the weight of the cover is not increased and means which adversely affect the visual appearance of the cover are not necessary, which is especially important where the cover is transparent. Optionally, the transmission means can be guided largely to the individual toggle joints on the frame.
When the movable transmission means is guided peripherally or continuously around a roof opening which is surrounded by a frame, by means of the uniform motion of the transmission means in one direction of motion, for example, in a forward motion, the first two pair of toggle joints can can be actuated or raised at the same time, and after a further path of movement of the transmission, the second pair of toggle joints are raised or actuated. By movement in the opposite direction (backwards motion) the toggle joints are actuated or retracted in the opposite motion sequence. Preferably, the transmission can be driven in a translational forward and backward motion. Depending on the arrangement and distribution of the toggle joints and the actuating elements along the frame, most any raising motions of the cover around different axes such as, for example, the lengthwise axes and transverse axes of the motor vehicle can be carried out.
The transmission is a cable, for example, a steel or a plastic cable. In alternative embodiments, the transmission is a chain, belt or wire spiral spindle as is used in the drive of sliding roofs, or a rod. To guide and deflect the transmission, for a cable or belt, deflection rollers, for a chain, gears, and for a wire spiral spindle, arc sections can be attached to the frame.
Preferably, the actuating elements are attached by force-fit and/or form-fit to the transmission means. On one cable, for example, actuating bodies can be pressed securely against intended locations. On one rod or chain, the actuating elements can be inserted into recesses and fixed therein.
Each toggle joint can comprise a pivoting toggle lever which has a defined engagement section for the respective actuating elements. This engagement section is matched to the shape and type of actuating elements used, which can be made, for example, as balls, ellipsoids or cylinders. The engagement section on the toggle contains, for example, a recess into which the respective actuating element can be moved by the transmission means. After engagement, the actuating element, which has continued to move, pivots the toggle lever into its other position.
For emergency opening of the hatch it can be provided that the connection of the toggle joint to the cover is made detachable. For example, the toggle lever is pivotally connected via an additional lever to the cover and the connection or support of this lever to the cover or on the cover is detachable for emergency opening of the cover. When the bearing pins which support the lever on the cover are released, on one of the two raising axes, the raising axis which is the other one at the time forms a folding axis of the cover for emergency opening. In this case additional safety elements for securing the cover to the hatch are not necessary.
Preferably, the transmission can be driven by a manually actuated drive unit or by a drive motor. For example, there can be two toggle joints which are paired with each other and which can be actuated at the same time by the actuating mechanism for raising the left and the right edge of the cover or for raising the front and the rear edge of the cover by means of a freely selectable, arrangement of the toggle joints on the frame and the associated actuating elements of the transmission, and the instant of raising and the raising sequence can be fixed by the number and the arrangement of actuating elements.
Accordingly, it can be provided that a second actuating element is assigned to the toggle joint which can be actuated first and resets the raised toggle joint in backward motion of the transmission before actuation of the other toggle joint.
Preferably, the transmission, and especially the cable, are pre-tensioned by spring force so that actuation takes place without play and reliable engagement of the actuating element with the toggle lever is ensured.
When the same types of toggle joints are used, the completely opened cover is roughly parallel to the frame, and thus, relative to the motor vehicle roof. According to one alternative embodiment, it can be provided that the completely opened cover can be set into a position which is not parallel to the frame by a different length and/or configuration of the toggle lever and/or the additional lever of a pair of toggle joints.
In the described hatch, the position of the cover can be set in the sequence xe2x80x9centirely closedxe2x80x9dxe2x86x92xe2x80x9crear upxe2x80x9dxe2x86x92xe2x80x9cfront upxe2x80x9dxe2x86x92xe2x80x9cback closedxe2x80x9dxe2x86x92xe2x80x9centirely closedxe2x80x9d or xe2x80x9centirely closedxe2x80x9dxe2x86x92xe2x80x9cfront upxe2x80x9dxe2x86x92xe2x80x9crear upxe2x80x9dxe2x86x92xe2x80x9cfront closedxe2x80x9dxe2x86x92xe2x80x9centirely closed.xe2x80x9d
One embodiment of the invention is detailed below with reference to the drawings.